1. Field of the Invention
Embodiments of the invention relates to the field of rule-based systems, and more specifically, to inference engines.
2. Description of Related Art
Inference engines are increasingly being used as a means to perform decisions in a wide variety of applications in business, science, engineering, etc. Typically, the decisions are formulated as a set of rules of the general form “if c then r” where c is a testable condition and r is an action. As conditions change, rules execute, or fire, when all of the conditions in c are met. The firing of a rule may result in either a change in the conditions of some other rule(s) or action(s) to modify the system, leading to an orderly and efficient execution of actions.
However, current inference system technologies are not well suited to the task of managing dynamic systems. A dynamic system is a system where actions are not performed merely on static events, but also on time-related events. Examples of time-sensitive rules are “If a disk error occurs more than three times in an hour, send a message to the tech center”, “If the disk error rule has fired within the last 24 hours, do not fire it again, even when the other conditions are met”.